The degasification of liquid sulfur which contain hydrogen sulfide has been described in German Patent No. 15 67 791 and British Patent No. 1,433,822. In these known techniques liquid sulfur which has been produced in sulfur-producing plants by the Claus process is treated to remove H.sub.2 S. That liquid sulfur contains hydrogen sulfide (H.sub.2 S) and polysulfides (H.sub.2 S.sub.x).
The transportation of such sulfur in a liquid state involves the risk that an atmosphere which contains H.sub.2 S may be formed in the gas space of the transport vehicle and that atmosphere may form an explosive mixture. Particularly, in steel containers an H.sub.2 S atmosphere may result in an explosion due at least in part to the formation of pyrophoric iron. For this reason the liquid sulfur which comes from the Claus process plant at an elevated temperature must be degasified as far as possible.
In the process of German Pat. No. 15 67 791 the liquid sulfur is sprayed into a chamber at a temperature of 125.degree. to 145.degree. C. Ammonia as a degasification accelerator is added to the sulfur before it is sprayed. The degasification accelerator serves mainly to convert the polysulfide to liquid hydrogen sulfide.
The British Patent No. 1,433,822 teaches that it is possible to use also air or diethanolamine as a degasification accelerator. The process in accordance with the British patent uses a vessel having two chambers and an overflow over which the treated sulfur flows from the first chamber into the second.